Building-block.



N0. 786,250. PATENTED MAR. 28, 1905.

' J. F. DUNHAM.

BUILDING BLOCK.

APPLICATION FILED 00w. 6, 1904.

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UNITED STATES Patented March 28, 1905.

PATENT OFFICE.

JAMES F. DUNHAM, OF WATERLOO, IOWA, ASSIGNOR, BY MESNE ASSIGN- MENTS, TOWVATERLOO CONCRETE BRICK & BLOCK MACHINE COM- PANY, OF l/VATERLOO, IOWA.

BUILDING-BLOCK- SPECIFICATION forming part of Letters Patent No.786,250, dated March 28, 1905.

Application filed October 6, 1904. Serial No. 2273M.

To (tZZ whom it may concern:

Be it known that I, J AMES F. DUNHAM, a citizen of the United States ofAmerica, and a resident of ater-loo, Blackhawk county, Iowa,have'invented certain new and useful Improvements in Building-Blocks, ofwhich the following is a specification.

My invention relates to improvements in building-blocks; and the objectof my invention is to so fashion a building-block that when in place inthe wall it will be securely tied therein and also have such openings orcommunicating passages, both vertical and horizontal, as will mosteffectually provide for the free circulation of air through all parts ofsaid wall. These objects I have effected by the means which arehereinafter described and claimed and which are fully illustrated in thedrawings hereto annexed, in which Figure 1 is a perspective view of myimproved building-block. Fig. 2 is a longitudinal vertical section ofthe same; and Fig. 3 is an end elevation of the same, while Figs. 4 and5 are alternative modes of shaping the end of the block.

Similar letters refer to similar parts throughout the several views.

The block a is provided with two similar apertures b and c, separated bya buttress (Z. The buttress (Z diminishes in Width from top to bottomand is made but a little longer than one-half the height of the block.The ends of the block are recessed, as shown, (2 being a V-shaped recessopen at the top and ends of the block. This recess 6 is filled Withcement when the block is laid in the Wall.

In Figs. 4 and 5 are represented the ends of blocks, one of which hasits V-shaped recess c of a semicircular contour, while the other has thesaid recess of a triangular contour. 4 The end walls are diminished inthickness from top to bottom. In order to provide horizontal series ofpassages through the wall, I have perforated the end walls of the block,

as shown at f, the bottom of the perforation being open and the sides ofthe perforation sloping from top to bottom. The effect is to furnish apassage longitudinally through the whole block, and when the blocks areconsecutively inserted in a wall there will be a se- 5 ries oflongitudinal horizontal passages therein as well as vertical ones. Thisfeature conduces to more perfect circulation of the air through theinterior spaces of the wall, and the general interruption of continuitybetween the inner and outer surfaces tends to effectually prevent theingress of moisture through the porous material of the blocks-a fault towhich the ordinary form of cement or concrete block is liable. Theperforations f at each end of the block also afford handholds to theworkman in lifting same.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is

A building-block provided with Vertical passages and longitudinalpassages open at the bottom, and having a V-shaped recess in each end,substantially as described.

Signed at Waterloo, Iowa, this 28th day of 7 September,

JAMES F. DUNHAM.

Witnesses:

G. C. KENNEDY, M. E. KENNEDY.

